If travelling through Winslow, AZ, be sure to stop at La Posada Hotel, if only just to look around.
Link here This was originally a hotel built by the Santa Fe railroad for their passengers. It was closed and then served as offices for the railroad until an enterprising family bought it and restored it. Very peaceful, lots of artwork, a fantastic high class restaurant. You might even want to abandon your RV for one night and spend a night in one of the rooms.
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The dining room:
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Travelling Rte. 66 is definitely worth it, although sometimes a somewhat melancholy experience. There are many great things to see, but on the other hand it is sad to see so many abandoned small diners, hotels, roadside attractions, etc. that were once flourishing but went under after the interstates came through. It is certainly interesting to see these, but sometimes sad too.